Obama May Create Earth's Biggest Ocean Sanctuary Would use executive authority to expand Bush-created monument By Matt Cantor, Newser User Posted Jun 17, 2014 7:28 AM CDT Updated Jun 17, 2014 7:59 AM CDT 100 comments Comments In this photo released by US Fish and Wildlife Service, butterfly fish swim near the Johnston Atoll, one of seven islands strung along the equator in the central Pacific Ocean. (AP Photo/NOAA, Jean Kenyon) (Newser) – In 2009, President Bush created an 87,000-square-mile marine sanctuary in the Pacific. Now, his successor wants to expand the Pacific Remote Islands Marine National Monument to 782,000 miles, a move that would double the area of protected ocean worldwide, the Washington Post reports. The marine sanctuary would be the world's biggest, surrounding seven US islands and atolls and stretching into waters up to 200 nautical miles off their coasts. President Obama is due to announce the proposal today; after a public comment period designed in part to "fully understand the commercial activity out there," he would use his executive powers to make it a reality later this year. Among the upsides: The number of underwater mountains being protected would increase five-fold, and five types of threatened sea turtles would be handed a safe haven. It would also safeguard what one National Geographic explorer-in-residence calls "the closest thing I've seen to the pristine ocean." But not all groups are likely to be pleased: The protections would ban energy exploration and fishing, and the region is responsible for some 3% of US-caught tuna in the western and central Pacific, the Post notes. Bush allowed sport fishing to continue in the area when he established the initial monument, and tuna fishermen are likely to raise opposition. Republicans are already doing so: "It’s another example of this imperial presidency,” says House natural resources chair Doc Hastings.